Culpability
by Spidershadow5
Summary: The Blackest Night has risen in Equestria. Celestia and Luna attempt to defend Canterlot castle until the Elements and their Lantern Corps arrive. But not all the dead are buried in the ground, and Luna must face her sins and fears if she wants to survive. Cover image by Berty-AJ on deviantart. One-shot.


Culpability

The dead had risen in Equestria.

The seemingly endless onslaught of Black Lanterns had made their way to Canterlot, laying siege to the city. Most of the citizens had, thankfully, been evacuated, but there were still targets for the dead to attack. Twilight and the other Elements, having gathered their respective Lantern Corps, were terminating as many Black Lanterns as possible, but they were still outnumbered.

Meanwhile, at the castle, both Celestia and Luna had ordered the Royal Guard to assist with the evacuation, refusing their offers to defend the castle. They were rulers, and it was their duty to protect their subjects with their very lives. At the moment, the alicorn sisters were battling the crowd of Black Lanterns, obliterating their rotting bodies over and over again, in an effort to stall for time.

"Go back to the shadow!" roared Luna, her horn covered by the massive magical blade she'd conjured. She swung her head in an arc, slicing through dozens of reanimated ponies, before charging a bolt of pure magic. She released the thunderous blast towards the bisected monsters, creating a midnight-blue explosion of light, and reducing the Black Lanterns to dust once more.

Luna paused, landing on the castle's roof and leaning against the brick for support. She glanced over, discovering Celestia in a similar state, panting as a yellow glow wavered around her horn. Even alicorn magic wasn't limitless. They couldn't keep this fight going forever. To make matters worse, both looked down at the ash remains of the Black Lanterns, only to see they were already starting to reform around the still intact black rings. Celestia grunted with anger, channeling her magic once more, and letting loose a shock wave, sending the rings flying off over the top of the castle, into the distance. But it was a temporary reprieve, and they both knew it.

"Any crazy ideas of yours, Lu?" asked Celestia, "Because at the moment, I'm all out."

"No," responded the night princess, struggling onto all four hooves once more, "We have to keep going. For the ponies. For Equestria."

"Naive. But that's expected," came a voice.

Celestia and Luna both whirled around. A Black Lantern pegasus, clad in ancient armor. The lightning bolt crest in the center of the chest plate had been filled with the symbol of the Black Lantern Corps, and the pony's Cutie Mark had been replaced by the same insignia. Behind him came another group of Black Lantern pegasi.

"Commander Hurricane, I presume," snorted Celestia, before letting loose a beam of magic. Hurricane flew into the air to dodge, then weaved to the side to avoid Luna's follow up shot.

 **[Rage. Will.]** said his black ring.

"You fight for a lost cause," snarled Hurricane, conjuring a war hammer out of black energy, "You cannot defeat us. We will restore this universe to order." He brought his new weapon down in an arc, and the sisters only had a second to dive to the side. The brick and mortar of the castle cracked from the weight of his blow.

"Keep talking," responded Luna, "We've probably heard it all before." She sliced downward in the air with her horn, sending a crescent shaped blast of energy toward Hurricane. The Black Lantern pegasus was unable to completely avoid it, but all it did was slice off his leg, which quickly regrew.

"Fools," he spat, as he dived towards the sisters, followed by his Black Lantern allies, "We are death. We are inevitable. We-"

He didn't get a chance to finish that sentence, as a massive spiked ball, formed entirely out of yellow energy, came flying out from the side of him, smashing the deceased pegasus against the wall and spilling his body parts in all directions. The other Black Lanterns turned to the source of the attack, only to be on the receiving end of several bolts of fear-powered energy.

"Princess Celestia! Princess Luna!" called Twilight, descending down from the sky to join her mentors, glowing with yellow light, "Are you okay?!"

Celestia breathed a sigh of relief. "We're fine for now, Twilight," she replied, sending another bolt of magic towards the Black Lanterns, "How is the battle going?"

"Fairly well," said the lavender alicorn, "Most of the civilians had been moved away from the battle, and we're trying to thin out the crowd of Black Lanterns. Applejack will be along in a moment, and we can wipe out the ones here."

"Tell her to hurry!" shouted Luna, sending another blue beam into the crowd of Black Lanterns, already starting to regenerate, "We can't hold them off much longer!"

Twilight spun around, her ring already igniting with the yellow glow of fear. Thinking back to a terrifying incident, she poured all her strength into it, the yellow energy spilling forth and beginning to mold into a shape. In seconds, Twilight had formed a gigantic Ursa Minor from the yellow energy, which lunged forward at her command, clamping it's jaws around the Black Lanterns. A few stragglers tried to flee, only for Celestia and Luna to blast them again, blowing them apart.

Unfortunately for everypony, they had missed one particular pony: Commander Hurricane. He hid in the shadows of the castle's towers, charging his black ring. Pulling his leg back, he fired a pair of black club constructs at Twilight and Celestia, knocking them backwards, and giving him the opening to fly past them and seize Luna's neck with both forelegs.

Luna grappled with the decaying pegasus, trying to maneuver her horn to cut him again. Hurricane solved this problem by conjuring up a small, skeletal arm, which grasped her horn and forcibly pushed it, along with her head, backwards. Luna roared in agony, the sensitive nature of a unicorn horn being used against her. Hurricane's lips morphed into something resembling a grin as her shoved her backwards into the brick wall.

"You realize this is your comeuppance, don't you, Luna?" he cackled, pushing down on her throat with his hoof, "You need to pay for your crimes. You need to pay for Nightmare Moon." In Hurricane's emotional vision, Luna glowed red and yellow.

 **[Rage. Fear.]**

"That's-gragh-that's not true!" Luna coughed out, trying to wrestle out of his grip, "I'm moved past that! It wasn't...my fault!"

 **[Emotional tether registered.]**

"That's not what your feelings are telling me," Hurricane laughed, "And that's all you need to do. Feel."

The zombified pegasus suddenly began retching, as though choking. Luna's eyes widened as black liquid poured forth from Hurricane's mouth, pouring over her body, splattering her wings and armor. From the gunk came a single black ring, which began orbiting Luna's head.

 **[Flesh.]**

"Wha-?!" Luna shouted, kicking Hurricane in the stomach with one hind leg, forcing him back. The ring continued to fly around her, buzzing like a fly, as though scanning for a body to possess inside of Luna. "I am not dead! What are-"

Then the ring changed course, flying right into Luna's chest, and phasing through the skin.

Luna's spine contorted as she screamed in agony. Her legs and wings began flailing, as her horn fired off random blasts of magic through her pain. She clutched her stomach as the ring moved not through her organs, but what felt like her very soul. In the distance, Celestia and Twilight tried to make their way over to protect her, only to be blocked and grabbed by the Black Lanterns. Hurricane merely floated in front Luna, laughing at her.

Then Luna heard the voice of the black ring speaking inside her.

 **[Nightmare Moon of Equis. Rise.]**

Luna felt her mouth swell as some sort of wet matter began to fill it. It was the most disgusting thing she'd ever tasted. It made her think of devouring a dead pony's flesh after maggots had already made their home in it. She vomited, spewing out more of the black goo Hurricane had released, along with the black ring. The piece of jewelry floated in the air for a second, the insignia glowing.

The black ooze levitated alongside the ring, forming a vaguely pony-like shape. It put one slimy tendril that might've been a leg through the ring. Decayed flesh began to spread across the slime, and a layer of pitch-black hair grew on top, though the hair was far more coarse than normal. Armor appeared on the creature's body, along with metal shoes and a helmet on the rounded tip that was becoming a head. Two spots of white gel in tiny pits began to grow, forming eyes, and a split below them formed a mouth with teeth growing inside it. A pair of wings, with skin so thin as to be nearly skeletal, burst from the developing creature's back, and a horn stabbed out of the rotting skin of the head. A Cutie Mark imprinted itself on the flank, resembling the Black Lantern symbol, but inside the triangle was a crescent moon.

Luna had to bite her tongue to avoid screaming in terror.

The Black Lantern Nightmare Moon was terrifying. She had not mane or tail, and her skin resembled that of a corpse that had been dead for several days. Her eyes had no pupils, leaving soulless white orbs sunken in their sockets. Her fangs were raw and rotting, but still sharp as daggers. Her midnight-blue coat was dyed the same black as the other reanimated ponies. She stared at Luna, and she smiled a terrible smile.

 **[Fear.]** said her ring.

"Well, well, well," laughed the undead Nightmare, "How low the mighty have fallen, eh, Luna?"

Luna's reflexes finally started to kick in, and she charged her horn for a magic blast. But it was far too late, as Nightmare Moon created a massive dragon claw construct. Princess Luna was punched backwards into the wall of the castle, causing it to shatter. Crumbling brick and mortar rained down into the throne room of Canterlot Castle, and Luna was sent bouncing across the floor. Each impact felt like another punch to her body, and she was sure she felt bones crack.

"Weak. The way you always were," said Nightmare Moon, following her doppelganger. She generated a rope of black energy, wrapping it around Luna's midsection and binding her wings to her sides. "Let's continue this conversation somewhere private, shall we?" The Black Lantern turned around and flew away from the castle, dragging Luna with her.

"LUNA!" Celestia screamed, decapitating another Black Lantern. She ignored Twilight's yells as she broke away from the crowd and began pushing herself with her wings, trying to follow her sister. But she'd barely made any distance when black tentacles sprang up behind her, seizing her legs and wings. Princess Celestia was brought down like a hammer, slamming into the courtyard with incredible force.

The solar alicorn grunted through the pain, fighting to keep her eyes open. She looked behind her to see her assailant. Another new Black Lantern, the tentacles emerging from his ring, floated down to greet her. This one was a unicorn, dressed in a wizard's cape and hat, with a long beard of ash-grey hair descending from his chin.

"Hello, Celestia," said Starswirl the Bearded, "Did you miss me?"

* * *

Nightmare Moon continued to drag Luna through the air, occasionally delivering a shock of Black Lantern energy to her captive, in case Luna tried to escape. She swung the rope like a mace on a chain, smashing Luna through trees and kicking up a swirl of dirt as she was driven through the grass. They finally came to a stop on the outskirts of Canterlot, Luna covered in earth and grass, with clumps caking onto bloody spots on her skin.

"I'm sure you missed me as much as I missed you," cackled Nightmare Moon, as she removed the rope construct, "Even if you tell yourself otherwise."

 **[Fear. Will. Rage.]** said the black ring.

Luna spat, her saliva mingling with blood. "That's...gah...you manipulated-"

"Oh, stop lying to everypony, Luna," said the Black Lantern, kicking the princess with one of her front legs. Luna uttered another grunt of pain. "You welcomed the shadows into your being. Because Celestia wouldn't listen to your concerns. Because she took all the respect of your subjects and you got nothing. You wanted to punish her. To make her suffer. To-"

A blast of magic from Luna's horn cut her off, severing her lower jaw. Luna charged forward like a berserker, stabbing her horn into Nightmare Moon's neck. She pulled, completely tearing off the Black Lantern's head, spilling rotten flesh between them. Not satisfied, Luna whirled around and bucked with all her might, sending Nightmare Moon's body flying backwards into a tree.

"You deceived me! You promised me respect, not tyranny!" Luna screamed, charging towards Nightmare Moon, "I never wanted eternal night! I never wanted to hurt Celestia!" Luna clubbed Nightmare Moon with her front hoof, bringing down the other for a direct stomp on the Black Lantern's chest.

Unfortunately for her, Nightmare Moon blocked it with her own hoof, pushing against her counterpart. Black energy swirled around the rotting hoof, forming tentacle appendages around it, like the fingers of a dragon. They dug into Luna's skin hard enough to draw blood, and the princess of the night lost all focus in the pain. Nightmare Moon took advantage of this by swinging her counterpart around, slamming Luna into the ground. Her regrown horn ignited with a glow as black as her skin, and Luna was telekinetically lifted into the air, before slamming repeatedly into the grass.

"Oh, you didn't intend those things to happen?" snorted the zombie, almost indignant, "This may be news for you, Luna, but things don't just happen because you 'mean' for them to." She created a massive black tentacle construct, wrapping it around Luna's neck and constricting, crushing the mare's windpipe. Nightmare Moon then punched her in the face over and over again with her front hooves. "You let me in, and in doing so, you gave up control. The destruction I wrought is on your head, no matter what you 'intended.'" She grabbed Luna by the chin, forcing the alicorn to face her. "And when I take your heart, I will go and rip out your sister's. Then I'll go and kill as many ponies as I can, and it will be your doing, because you created me." She grinned again, the rotting muscles stretching with a sickening squelch. "How does that make you feel?"

Luna seemed to freeze with an expression of anguish on her face, like those who died in the worst possible way. She didn't even blink as tears dripped from her eyes. Through her emotional vision, Nightmare Moon saw that Luna was completely covered by the indigo and violet auras of compassion and love. The Black Lantern laughed one more time, reaching for Luna's heart with her other hoof.

Then Luna's aura faded.

Nightmare Moon's dead eyes widened in shock, as Luna took a breath through the constricting force on her throat. She closed her eyes, and her lips covered her mouth. For a pony being choked, she looked almost peaceful. Nightmare Moon saw Luna filling up with emotion again, only this time it was green.

 **[Will.]**

"Yes...I created Nightmare Moon," said Luna, a calm tone surrounding her words, "She existed because I let the darkness in. But I've moved on from my actions as Nightmare Moon. Twilight and the others taught me to forgive myself. What matters is what is happening now." She stared right into Nightmare Moon's eyes. "You are not her. Your a projection created by the black ring." The magical blade projected from Luna's horn once more, and she sliced off Nightmare Moon's head. "And I will stop you."

* * *

Celestia roared in agony as another bolt from the Black Lantern Starswirl slammed her into the brick wall. The zombified unicorn cackled as he conjured up a massive dragon head of black energy. Celestia managed to recover enough to launch a beam of golden energy, pushing the head back, but it clearly wasn't enough. Then Twilight brought on her own assault, summoning a giant yellow dragon and bathing Starswirl, his creation, and his black lantern allies in yellow fire.

"I'm giving it everything, Celestia!" shouted Twilight, "But I can't destroy their rings without a Green Lantern!"

"Ah got ya, Sugar Cube!" shouted a new voice.

Applejack zoomed onto the scene in a burst of green light. Her ring of willpower radiated like a torch, adding a beam of her own light to Twilight's. The Black Lantern Starswirl screeched as the twofold assault of fear and will wrapped around his ring, beating on it and cracking it into pieces. The other Black Lanterns met the same fate, despite their attempts to flee. With a final snap, their rings shattered, and the bodies disintegrated into dust.

 **[Connection severed.]** said the rings in their death throes.

"What took you so long?!" demanded Twilight, floated up to her friend, "The Black Lanterns have been swarming around the castle!"

"Sorry about that. Some of them went after the ponies we were evacuatin'," responded Applejack, "Rarity couldn't pull enough green light to take 'em all."

Celestia pushed herself out of the cavity she'd created in the brick. "Applejack, you have to help us! They created a Black Lantern Nightmare Moon, it took Luna-!"

"On it, Princess!" said Applejack, "Ring, find-"

She never got to finish the command, as her ring began vibrating. Applejack couldn't hold her leg still as the object rumbled. The familiar bright green glow formed without any of her input as she, Twilight, and Celestia looked on.

 **[Sentient of immense willpower detected. Scanning.]** reported the ring. **[Sentient identified. Luna of Equis.]**

"What?" asked Twilight, "What's it doing now?"

 **[Duplicating.]** said the ring. The green glow intensified, shining like a star before it seemed to fade. Suddenly, a new green ring burst out of the center of the Applejack's. The new piece of jewelry floated in the air for about a second, before making an abrupt turn and taking off towards the outskirts of Canterlot.

"Is it...going after Luna?" asked Celestia, shocked.

"Follow it!" yelled Applejack, zooming after the ring, the other two in close pursuit.

* * *

Luna and Nightmare Moon continued their battle, their magic laying waste to the surrounding landscape. Nightmare Moon continued to taunt Luna, but the princess of the night put her focus into ignoring her opponent's words, and her brain was concerned with absolutely nothing but the battle at hand.

"Okay, fine," snorted Nightmare Moon, "Just use your will. You still have no means to defeat me, and I can still take that emotion in your heart-"

She was cut off by a beam of green light from behind her, punching a hole through her head, right between the eyes. Luna charged up her shield as the beam swerved towards her, but stopped when she discovered the truth. It wasn't a simple energy beam, but a green ring trailing it's signature light behind it. The ring swirled around Luna's head, the way the black ring had.

 **[Luna of Equis. You have the ability to overcome great fear.]** said the ring. Suddenly, it changed course and latched onto her front leg. **[Welcome to the Green Lantern Corps.]**

A blinding burst of green light lit up the landscape, blinding Nightmare Moon and eclipsing Luna. Once the light faded, the Black Lantern opened her eyes to see Luna, suited up as a Green Lantern. The princess' body was now covered by a black suit, with green boots, and a green collar. On the front, right between her legs, lay the symbol of the Green Lanterns, burning bright from Luna's strength of will.

"Impossible..." breathed the Black Lantern.

"I disagree," retorted Luna, raising her new ring. Green energy flowed forth, forming constructs of Celestia, Twilight, the other Elements of Harmony, and Spike. All the Elements were wearing construct versions of their necklaces, along with Twilight's crown. While the versions of Spike and Celestia opened fire with magic and flames, the Elements of Harmony unleashed the rainbow beam, although this one was pure green. Luna added her own beam, combining her magic beam with the power of the green ring.

Nightmare Moon was blasted in multiple different places, ripping holes in her rotting body, sending shreds of skin falling down to the grass. Her head was split in half by the rainbow beam, and Luna's blast hit the spot where her heart would've been, searing her so much that her leg was severed.

"You think you can win like this?!" snarled Nightmare Moon, her mouth barely intact enough to speak, "You will can't turn back the dark! I will-"

Another blast of green energy cut her off, decapitating Nightmare Moon completely. This was followed by a burst of yellow light, mingling with that of the two Green Lanterns. Nightmare Moon's ring was assaulted by the combined light, and split in two with a resounding crack. Her body followed, dissolving into nothing but ash.

Luna looked up to see Applejack and Twilight floating in the air, their rings blaring light, staring at her, along with her sister. Celestia wasted no time in pushing past the other two, rushing over to her sister and throwing her front legs around her.

"Oh, Luna, Luna," breathed the white alicorn, "You're okay, you're safe..."

"It's okay, Tia," said Luna, returning the hug. She looked at her sister, noticing the bloody gashes where she'd been slammed into the brick wall. "Are you alright?"

"Nothin' Pinkie's blue ring can't fix," said Applejack, dropping down next to the pair, "Wow, Princess, I didn't know you had it in you."

"Neither did I," said Luna, looking thoughtfully at her green ring, "But then why did you send this to me?"

"She didn't," explained Twilight, "Apparently, your surge of willpower was so strong that it compelled her ring to duplicate itself and deputize you."

"Luna," said Celestia, "What did she...it do to you?"

"It doesn't matter," Luna replied. She held up her ring, conjuring up a green hole in the air. Her magical grip reached through, plucking out her new power battery. "We have work to do."


End file.
